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Brigham Young University

2017

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Articles 31 - 60 of 174

Full-Text Articles in Life Sciences

The Relationship Between Microbiota, Diet, And Energy Production In The Alpaca, Courtney Carroll Aug 2017

The Relationship Between Microbiota, Diet, And Energy Production In The Alpaca, Courtney Carroll

Theses and Dissertations

The alpaca is a small South American camelid (SAC) that is an important production animal in Peru, especially among the highly impoverished communities of the high Andes, and raised for its fiber and meat. Alpacas are highly reliant on the microbes within their digestive tracts to digest the plant material they consume; volatile fatty acids (VFAs) are released as a byproduct of this microbial fermentation and used as a major source of energy by the alpaca. To explore optimal parameters for alpaca microbiome analysis, performed 16S rRNA gene surveys on alpaca C1 and fecal samples that had been extracted using …


Byu Undergraduate Explore The Development Of Scientific Reasoning Ability In Stem Majors And Its Correlation To Student Performance And Retention, Jamie Jensen Jul 2017

Byu Undergraduate Explore The Development Of Scientific Reasoning Ability In Stem Majors And Its Correlation To Student Performance And Retention, Jamie Jensen

Journal of Undergraduate Research

This report will outline how effectively we met our academic and mentoring objectives. I have listed below both the academic and mentoring objectives put forth in the original proposal and have outlined how they were met or modified over the course of the past two years. Let me just start out by saying how proud I am of my undergraduate team of researchers. They have been absolutely AMAZING and have taken this project on with incredible autonomy. Although we are a bit behind our anticipated schedule (due to the autonomy that I have tried to foster with the students), the …


Insect Visual Systems And Fossils To Provide Students A Clear Vision Of 21st Century Phylogenetic Systematics, Seth M. Bybee Jul 2017

Insect Visual Systems And Fossils To Provide Students A Clear Vision Of 21st Century Phylogenetic Systematics, Seth M. Bybee

Journal of Undergraduate Research

Goals one and three were both very successful (more below), however goal two became bogged down and was ultimately abandoned. CT-scanning is a process that requires hundreds or even thousands of fine x-rays through an organism in cross-section to be “stacked” together. Stacking the x-rays together allows researchers to literally explore the internal and external anatomy of organisms in ways never before possible. The most successful scans are those produced when tissues are discrete and have different attributes in terms of pattern, hardness, etc. We focused heavily on fossil specimens embedded in amber. Unfortunately, the cuticle of these specimens were …


Autoimmunity-Promoting B Cell Effects Of The Risk Factor Irf5, Brian Poole Jul 2017

Autoimmunity-Promoting B Cell Effects Of The Risk Factor Irf5, Brian Poole

Journal of Undergraduate Research

The academic objectives of this proposal were met. Using the funding provided by the MEG, we generated data that were used to publish two peer-reviewed journal articles:


The Role Of Nr4a1 In Maternal Obesity Induced Beta Cell Expansion, Jeffery S. Tessem Jul 2017

The Role Of Nr4a1 In Maternal Obesity Induced Beta Cell Expansion, Jeffery S. Tessem

Journal of Undergraduate Research

The academic objectives of this Mentoring Environment Grant (MEG) were to 1) train undergraduate students in the scientific process to prepare them in careers as physicians and scientists, and 2) to examine the relationship between in utero Nr4a1 beta cell specific deletion during maternal overnutrition and obesity on beta cell mass at birth and diabetic onset. We were successful in accomplishing these objectives, as evidenced by the training of four undergraduate students, presentation of research and local and national meetings, and initial preparation of a manuscript reporting our findings.


Final Report For The 2015 Meg Entitled: Development Of Real-Time Polymerase Chain Reaction (Q-Pcr) Assays For The Detection And Identification Of Human Tick-Borne Pathogens, Richard Robison Jul 2017

Final Report For The 2015 Meg Entitled: Development Of Real-Time Polymerase Chain Reaction (Q-Pcr) Assays For The Detection And Identification Of Human Tick-Borne Pathogens, Richard Robison

Journal of Undergraduate Research

  1. Develop singleplex q-PCR assays to identify the tick-borne pathogens Borrelia burgdorferi, Borrelia hermsii, Bartonella henselae, and Babesia microti. Primer generation software will be used to design primer and probe sequences that will theoretically perform optimally in PCR reactions. All sequences will be subjected to BLAST searches to confirm their specificity for a particular organism. Once primer sequences have been obtained, they will be synthesized by Integrated DNA Technologies, Inc. (IDT). These primers will be evaluated in q-PCR reactions using target DNA from multiple isolates and SyberGreen to detect nucleic acid amplification. Parameters for each reaction will be optimized using these …


Synaptic Modification Of Inhibitory Inputs To Gaba Neurons In The Ventral Tegmental Area: A Novel Potential Target Mediating Reward And Addiction In The Brain, Jeff Edwards Jul 2017

Synaptic Modification Of Inhibitory Inputs To Gaba Neurons In The Ventral Tegmental Area: A Novel Potential Target Mediating Reward And Addiction In The Brain, Jeff Edwards

Journal of Undergraduate Research

The objectives of this award were met, especially in regard to the mentoring focus of the award. The students have been mentored and trained in an effective manner as outlined in my Mentoring Plan (abbreviated below). This includes mentoring students in research, writing, publishing, presenting at conferences, etc. Indeed, one measure of the success of mentoring is demonstrated by the fact that all the students graduating from my lab during this time were accepted to the professional school of their choice (see students listed below). Research, especially where the students are actually involved in all aspects of it including data …


Unleashing The Power Of Undergraduates To Unravel The Impacts Of Water Relations And Co2 Levels On The Photosynthetic Plasticity Of Agave Sensu Lato Species: A Group Of Desert Succulents Important To Natural And Human Systems, J. Ryan Stewart Jul 2017

Unleashing The Power Of Undergraduates To Unravel The Impacts Of Water Relations And Co2 Levels On The Photosynthetic Plasticity Of Agave Sensu Lato Species: A Group Of Desert Succulents Important To Natural And Human Systems, J. Ryan Stewart

Journal of Undergraduate Research

  • Evaluation of how well the academic objectives of the proposal were met
  • Evaluation of the mentoring environment
  • List of students who participated and what academic deliverables they have produced or it is anticipated they will produce
  • Description of the results/findings of the project
  • Description of how the budget was spent


The Role Of Lkb1 In Obesity-Induced Skeletal Muscle Inflammation And Insulin Resistance, David Thomson Jul 2017

The Role Of Lkb1 In Obesity-Induced Skeletal Muscle Inflammation And Insulin Resistance, David Thomson

Journal of Undergraduate Research

The incidence of obesity and the health consequences that accompany it have increased rapidly over the past decade. Understanding the molecular pathways involved in its development will be crucial in developing novel treatment strategies for obesity and associated disorders. Low-grade inflammation likely plays a major role in many of the complications of obesity. We proposed to study the role of liver kinase B1 (LKB1) in the development of inflammation and insulin resistance in obese mice and saturated fatty acid-induced insulin-resistant cells.


Effects Of Curcumin And Ursolic Acid On The Mitochondrial Coupling Efficiency And Hydrogen Peroxide Emission Of Intact Skeletal Myoblasts, Daniel J. Tueller Jul 2017

Effects Of Curcumin And Ursolic Acid On The Mitochondrial Coupling Efficiency And Hydrogen Peroxide Emission Of Intact Skeletal Myoblasts, Daniel J. Tueller

Theses and Dissertations

Curcumin is a natural compound that improves blood glucose management. While some evidence from isolated mitochondria indicates that curcumin uncouples electron transport from oxidative phosphorylation, the effects of curcumin on mitochondrial respiration and hydrogen peroxide emission in intact skeletal muscle cells are not known. By assessing rates of oxygen consumption, we demonstrated for the first time that curcumin (40 µM) reduced the mitochondrial coupling efficiency (percentage of oxygen consumption that supports ATP synthesis) of intact skeletal muscle cells. A 30-minute incubation with curcumin decreased mitochondrial coupling efficiency by 17.0 ± 0.4% relative to vehicle (p < 0.008). Curcumin also decreased the rate of hydrogen peroxide emission by 43 ± 13% compared to vehicle (p < 0.05). Analysis of cell respiration in the presence of curcumin revealed a 40 ± 4% increase in the rate of oxygen consumption upon curcumin administration (p < 0.05 compared to vehicle). In additional experiments, no difference in mitochondrial coupling efficiency was observed between vehicle- and curcumin-pretreated cells after permeabilization of cell membranes (p > 0.7). The possibility of synergistic …


Response To Drought Of A Stream Fish Assemblage In A High Elevation Stream In The Intermountain West, Richard M. Simkins Jul 2017

Response To Drought Of A Stream Fish Assemblage In A High Elevation Stream In The Intermountain West, Richard M. Simkins

Theses and Dissertations

One of the most influential disturbances for stream fish assemblages is large-scale declines in flow caused by periods of drought. Although stream characteristics are known to influence the response of stream fishes to drought, we asked if ecological traits of stream fishes determine, in part, their population level response to drought. To test for ecological trait-based responses to drought in a stream fish assemblage, we quantified species abundances over a period of 5 years that represented a wet to dry period. We sampled stream fishes in Yellow Creek, Wyoming, USA, a high elevation stream dependent on snow-storage for most of …


Sagittal Abdominal Diameter, Waist Circumference, And Bmi As Predictors Of Multiple Measures Of Glucose Metabolism: An Nhanes Investigation Of U.S. Adults, Shelby Anne Firouzi Jul 2017

Sagittal Abdominal Diameter, Waist Circumference, And Bmi As Predictors Of Multiple Measures Of Glucose Metabolism: An Nhanes Investigation Of U.S. Adults, Shelby Anne Firouzi

Theses and Dissertations

OBJECTIVE: The key objective of the present investigation was to compare associations between sagittal abdominal diameter (SAD), waist circumference, and BMI to the oral glucose tolerance test (OGTT), along with fasting glucose, HbA1c, and HOMA-IR, in a nationally representative sample of U.S. adults. The study also analyzed the effect of multiple covariates on the anthropometric and glucose metabolism associations. METHODS: A cross-sectional design, including 3,582 subjects, was used. SAD was assessed using an abdominal caliper. All other data were collected following strict NHANES protocol. The OGTT was the primary variable used to index glucose metabolism. Fasting glucose, HbA1c, and HOMA-IR …


Bacterial Community Ecology Of The Colon In Mus Musculus, Rachel Marie Nettles Jul 2017

Bacterial Community Ecology Of The Colon In Mus Musculus, Rachel Marie Nettles

Theses and Dissertations

The gut microbiome is a community of closely interacting microbes living in the gastrointestinal tract. Its structure has direct relevance to health. Disturbances to the microbiome, such as due to antibiotic use, have been implicated in various diseases. The goal of this study was to determine how the gut microbiome reacts to and recovers from disturbance caused by antibiotics. Because diet also influences the microbiome, this study included the interaction between diet and antibiotics. Half of the mice in each diet treatment were given antibiotics to disturb their microbiomes. After cessation of antibiotics, mice were paired in combinations within diets …


Modulation Of Synaptic Plasticity: Endocannabinoids And Novel G-Protein Coupled Receptors Expression And Translational Effects In Interneurons, Katrina M. Hurst Jul 2017

Modulation Of Synaptic Plasticity: Endocannabinoids And Novel G-Protein Coupled Receptors Expression And Translational Effects In Interneurons, Katrina M. Hurst

Theses and Dissertations

Learning and memory are important processes that occur in the brain. The brain is comprised of neurons that make connections with each other known as synapses. Synaptic plasticity is widely believed to be the physiologic mechanism by which learning and memory occur. Synapses can either be strengthened through a process known as long-term potentiation (LTP) or weakened through long-term depression (LTD). The area of the brain that is most studied for its role in learning and memory is the hippocampus, which has been shown to be involved in memory consolidation. The detection of endocannabinoids and their receptors has opened a …


Role Of Terrestrial Organic Matter In Food Webs Of The Rocky Intertidal Zone, Douglas O. Fairbanks Jul 2017

Role Of Terrestrial Organic Matter In Food Webs Of The Rocky Intertidal Zone, Douglas O. Fairbanks

Theses and Dissertations

Terrestrial organic matter (TOM) constitutes an important source of energy in many aquatic environments (streams, lakes, wetlands). This is the first study to examine the role of TOM in food webs of the rocky intertidal zone. We compared the consumption of red alder leaves (Alnus rubra) to common marine sources of drifting detritus along the southern Oregon coast (Nereocystis luetkeana, Phyllospadix spp., and Fucus gardneri). We used short term (hours to days) and long term (months) feeding experiments to compare the rate of consumption among each plant species during the Spring and Fall of 2014 …


The Relationship Between Generalized Joint Laxity And Hip Cartilage Thickness In Ballet And Modern Dancers, Noelle Jeanette Tuttle Jul 2017

The Relationship Between Generalized Joint Laxity And Hip Cartilage Thickness In Ballet And Modern Dancers, Noelle Jeanette Tuttle

Theses and Dissertations

Generalized joint laxity (GJL), a condition in which most joints of the body move beyond the accepted normal range of motion, is present in many ballet and modern dancers. It has been associated with an increased risk of injury, decreased muscle strength, and greater landing forces. Increased joint laxity results in joint instability and may precede the development of osteoarthritis, which is associated with a reduction in cartilage thickness. We hypothesized that dancers with GJL would have decreased hip cartilage thickness, as well as greater hip adduction angles and greater ground reaction force on landings. Twenty female ballet and modern …


Β-Cell Adaptation To Decreased Nr4a Expression In Conditions Of Elevated Palmitate Concentrations (Hyperlipidemia), Daniel Lathen, Jeffery Tessem Jun 2017

Β-Cell Adaptation To Decreased Nr4a Expression In Conditions Of Elevated Palmitate Concentrations (Hyperlipidemia), Daniel Lathen, Jeffery Tessem

Journal of Undergraduate Research

Diabetes’ prevalence is increasing at an alarming rate. Normally, insulin-secreting β-cells in the pancreas regulate proper glucose absorption and storage. Both Type 1 and Type 2 diabetes are characterized by decreased functional β-cell mass and insulin production and increased circulating glucose and fatty acid levels, which damage and destroy surviving β-cells over time. Though hyperlipidemia’s short-term effects are well studied, its long-term effects on β-cells remain unclear because it destroys them (1). We developed unique cell lines to mimic Type 2 diabetes’ progression by culturing INS-1 832/13 β-cells in progressively elevated concentrations of palmitate (a saturated fatty acid), which permitted …


The Role Of Nr4a1 In Β-Cell Glucose Stimulated Insulin Secretion And Cellular Survival, Kevin Garland, Jeffery Tessem Jun 2017

The Role Of Nr4a1 In Β-Cell Glucose Stimulated Insulin Secretion And Cellular Survival, Kevin Garland, Jeffery Tessem

Journal of Undergraduate Research

In 2010, diabetes was the 7th leading cause of death in America, and as of 2014, 9% of the world’s adult population was affected by it. In both Type I (T1D) and Type II diabetes (T2D), a loss of β-cell mass and overall function is observed. β-cells essentially stop proliferating after adolescence, therefore developing mechanisms to increase function and/or induce proliferation in β-cells could serve as a powerful treatment and even a cure for both T1D and T2D. Overexpression of the β-cell transcription factor Nkx6.1 induces β-cell proliferation (1) and up-regulates expression of the nuclear receptor Nr4a1 (2). Nr4a1 has …


Development And Application Of Minimum Energy Crossing Point Software Suite For Organometallic Reactions, Justin Snyder, Daniel H. Ess Jun 2017

Development And Application Of Minimum Energy Crossing Point Software Suite For Organometallic Reactions, Justin Snyder, Daniel H. Ess

Journal of Undergraduate Research

Computational studies are critical to the field of organometallic chemistry since many highly reactive and unstable compounds cannot be isolated or observed experimentally. It is well-known that many organometallic reaction mechanisms involve spin intersystem crossing, e.g. singlet to triplet conversion. To estimate the rate of intersystem crossing it is useful to calculate electronic structures where spin states and their energies are degenerate, which is called a “minimum energy crossing point (MECP).” Prior to the completion of this project, there was only one working program that interfaced with the Gaussian 09 electronic structure package for the calculation of minimum energy which …


Electronic Structure And Quassiclassical Dynamics Of [2+2] Tetrafluoroethylene Cycloaddition Reactions, Steven Jones, Daniel Ess Jun 2017

Electronic Structure And Quassiclassical Dynamics Of [2+2] Tetrafluoroethylene Cycloaddition Reactions, Steven Jones, Daniel Ess

Journal of Undergraduate Research

Cycloaddition reactions are key reactions used to construct complex cyclic scaffolds (large networks of carbon atoms that can be used in catalysis, synthesis, etc.). While classical reactions that form 6-membered rings are well-known and generally have a one-step reaction mechanism, 4-member ring-forming reactions are much less used, but could be very valuable for the construction of cyclobutane structures.

Tetrafluoroethylene (TFE) is used on a large scale by Dow and other chemical companies to form hydrofluoro compounds such as teflon. The current understanding of the mechanism of cycloaddition reactions with TFE is limited. Standard hydrocarbon reactions proceed via a welldocumented, concerted …


Defining Nkx6.1 Binding Partners In Young And Aged Pancreatic Islet, Sean Kang, Dr. Jeffery Tessem Jun 2017

Defining Nkx6.1 Binding Partners In Young And Aged Pancreatic Islet, Sean Kang, Dr. Jeffery Tessem

Journal of Undergraduate Research

Diabetes is an increasing epidemic that deserves more attention. Those affected by diabetes are restricted to either strict diets or remedial insulin supplementation. Both Type 1 and Type 2 diabetes are directly related to a decrease in functional β-cell mass. Exciting research has revealed Nkx6.1 to be an influential transcription factor which induces β-cell proliferation, protects against apoptosis and enhances insulin secretion when overexpressed 1 . Our recent findings indicate significant β-cell proliferation is limited to β-cells from adolescent rats, with a severe decrease in proliferation as the animal ages. 2 Nkx6.1 expression is present in every stage of development, …


Microwave Promoted Iminyl Radical Cyclization, Aaron Kubosumi, Steven L. Castle Jun 2017

Microwave Promoted Iminyl Radical Cyclization, Aaron Kubosumi, Steven L. Castle

Journal of Undergraduate Research

Pyrrolidines and their derivatives are found in many biologically active compounds, such as Lipitor and Atorvastatin, which possess a wide variety of remarkable pharmaceutical properties. Therefore, the efficient synthesis of functionalized pyrrolidines is of great value to organic chemists. Multiple attempts have been made to synthesize compounds containing pyrrolidine ring systems. Walton 1 utilized radical cyclization, via microwave heating, to transform Ophenyl oximes with terminal alkenes to dihydropyrroles, compounds closely related to pyrrolidines. Similarly, Sammis 2 proposed a method involving radical cyclizations of azidederived aminyl radicals onto silyl enol ethers. Unfortunately, the method proposed by Sammis requires highly toxic and …


Current And Future Prospects Of The Biological Diversity Of Vertebrates In Teh Protected Areas Of A Megadiverse Country: Ecuador, Benjamin Bay, Dr. Jack Sites Jun 2017

Current And Future Prospects Of The Biological Diversity Of Vertebrates In Teh Protected Areas Of A Megadiverse Country: Ecuador, Benjamin Bay, Dr. Jack Sites

Journal of Undergraduate Research

I collected, cleaned, and organized data on animal species in Ecuador, a megadiverse country (harbors a vast proportion of Earth’s species and is home to high numbers of endemic species). These data were crucial for a larger project which modeled the impacts of climate change on species conservation over time. I designed the algorithms that cleaned and organized these large data sets.


Cebp/Α Increases Functional Β-Cell Mass, Jason Ray, Jeffery Tessem Jun 2017

Cebp/Α Increases Functional Β-Cell Mass, Jason Ray, Jeffery Tessem

Journal of Undergraduate Research

Type 1 and Type 2 diabetes are major global health concerns. Diabetes is characterized by impaired management of glucose in the bloodstream, which is due to decreased pancreatic functional β-cell mass. Functional β-cell mass is determined from the insulin secretion rate and the number of β-cells, which is determined from cellular proliferation and death rates. Increasing functional β-cell mass could cure diabetes either by enhancing pancreatic islets prior to transplantation, or by strengthening endogenous cells. Although β-cells stop proliferating around adolescence, β-cell proliferation resumes during conditions such as pregnancy and obesity (1), demonstrating that the molecular pathways necessary for replication …


Quantifying The Efficiency Of Heterobimetallic Complexes, Ryjul Stokes, David Michaelis Jun 2017

Quantifying The Efficiency Of Heterobimetallic Complexes, Ryjul Stokes, David Michaelis

Journal of Undergraduate Research

Transition metal catalysts have revolutionized the efficiency by which pharmaceuticals and other value added products are synthesized due to their unique ability to activate small molecules and drive the formation of new C-C and C-N bonds. In particular, the direct functionalization of olefins with transition metal catalysts is a powerful method of converting simple, cheap building blocks into more complex molecules. The challenge is that many ligands that control reaction selectivity often decrease the electrophilicity of the catalyst. Heterobimetallic complexes containing an early/late transition metal pair could provide a solution to this challenge by providing a new way to activate …


Determining The Structure Of The Bbbsome, Grant Ludlam, Barry Willardson Jun 2017

Determining The Structure Of The Bbbsome, Grant Ludlam, Barry Willardson

Journal of Undergraduate Research

Bardet-Biedl Syndrome (BBS) occurs when an eight-protein complex called the BBSome is improperly assembled and can no longer function. The BBSome is responsible for trafficking membrane proteins to cilia, a projection from the cell surface packed with receptors that allow the cell to sense its surroundings. Loss of BBSome function causes malformation of cilia and leads to vision loss, obesity, kidney disease and mental retardation.


The Total Synthesis Of Yaku’Mide A, Shi Luo, Steven Castle Jun 2017

The Total Synthesis Of Yaku’Mide A, Shi Luo, Steven Castle

Journal of Undergraduate Research

Yaku’amide A (YA) has potent toxicity against cancer cells (IC50 = 14 ng/ml against P388 murine leukemia cells). Ueoka et al.1 first reported the isolation of YA from a marine sponge in the East China Sea. They used spectroscopy and chemical degradations to analyze its structure. YA contains unique dehydroamino acids (See Figure 1). In the growth inhibition study, YA showed unique activity against 39 cancer cell lines, indicating a novel mode of action. The unusual structure of YA and its prominent biological activity has attracted research groups from around the world to address its synthesis.


Using Three Incommensurate Wave Components To Generate Terahertz Radiation, Jacob Bagley, Jeremy Johnson Jun 2017

Using Three Incommensurate Wave Components To Generate Terahertz Radiation, Jacob Bagley, Jeremy Johnson

Journal of Undergraduate Research

Electromagnetic radiation is a wave composed of an electric field and a magnetic field. Examples of electromagnetic radiation include visible light, ultraviolet light, Xrays, infrared light, microwaves, and more. Electromagnetic radiation is an indispensable tool for both controlling and studying matter and is applied to countless fields such as electronics manufacturing and medical imaging. Over the past two decades terahertz (THz) radiation, a form of electromagnetic radiation, has become an intense area of research. This surge in activity in due in part to technological advances in generating THz radiation, but is also due to the myriad of potential applications of …


A Microfluidic Approach To Measuring Endothelial Cell Migration Jun 2017

A Microfluidic Approach To Measuring Endothelial Cell Migration

Journal of Undergraduate Research

Pathological angiogenesis or new vessel growth plays a key role in a number of diseases including tumor growth and several eye diseases that can lead to blindness. While antiangiogenic therapies have been developed for many of these pathologies, there remains a pressing need for more effective anti-angiogenic therapy with fewer side-effects. Capillary morphogenesis gene 2 (CMG2) has been shown to play an important role in angiogenesis and is a potential target for future anti-angiogenic therapies. To better understand the physiological role of CMG2 and to accurately compare how well different CMG2 antagonists inhibit endothelial cell migration (the putative mechanism for …


Elucidation Of Mechanisms Whereby Embryonic Chicken Limbs Develop, James Broadbent, Jeffery Barrow Jun 2017

Elucidation Of Mechanisms Whereby Embryonic Chicken Limbs Develop, James Broadbent, Jeffery Barrow

Journal of Undergraduate Research

As established by John Saunders 60 years ago, the AER is required for limb growth and patterning. However, the mechanisms whereby the AER regulates these processes remain poorly understood. My professor and I propose that one of the primary roles of the AER is to regulate directional growth of the adjacent limb mesenchyme. Over time, the AER extends along the anteroposterior (AP) and thins along the dorsoventral (DV) axes. These results highlight a morphogenetic paradigm: the dimensions of recruitment signaling centers ultimately shape organs. This model also provides mechanistic insight for evolutionary change. We also show that sonic hedgehog (Shh) …